After at least 3 rooms of monsters, you will reach the boss.Its a random of 3 bosses, either unicorn-lion, nergel or lunia.Lunia's the strongest and the hardest one of out them.Just stay behind lunia most of the time when she casts any spell.Play more to get to know more. Experience is key here. xD

Okay. So after u kill the boss, a chest will appear. A random lottery will show up and the player with the highest number wins the chest. Only killing lunia will you get the Lunia Spirit box. The other two bosses give the Lunia Incarnation box.These boxes have a rare chance to open into another box, or open into soul of moons.